Help us with our 70 hp 1975 Evinrude

[catfishindylan]

Last summer we took it out fishing one night, and about 1 hour moving down the lake it shut ,off and was releasing steam so im sure it was hot

Before we took it out 2 weeks ago for a test run , it had been siting in the garadge for 5 months. So it took a while to get it to full power on the test run.

The reason we had taken it out for a test run was because it had never ceized up and started in the garage a week after it had stopped on the lake last summer.Our neibor a mechanik on cars said tht if it had never ceized up it should be fine. But anyways when we had taken it out on the test run it took a while to get it to full power than when my dad finnaly got to full power and switced gears from reverse to forward it would shut off.

So my dad thought about it and he thought at first tht we may have allinged the lining wrong, but now he thinks it could be something with a piston , so idk wat to do if someone could help us out that would be awsome.

 

[ezmobee]

Re: Help us with our 70 hp 1975 Evinrude

Did you do anything to address why it may have overheated the first time?

 

[catfishindylan]

Re: Help us with our 70 hp 1975 Evinrude

it only overheated once and that was 5 months ago, 2 weeks after it had over heated, my dad started it in the garagde just fine.

We replaced the old water pump with a new one a few months later.

But now our problem is that whenever you switch from reverse to forward it shuts off.

 

[ezeke]

Re: Help us with our 70 hp 1975 Evinrude

You are probably dropping a cylinder, so you need to do a compression test and a spark test.

Instructions for a compression test are in the "Top Secret" file at the top of this forum.

A spark test is performed with all sparkplugs removed, using a test device capable of a 7/16 gap.

BTW, whenever you have an overheat, it's good shop practice to replace the cylinder head gasket and re-torque the cylinder head bolts after the gasket seats.